ting). Before reaching and passing through the holes in the
die, the material is filtered through a disk of fine wire gauze to
retain any foreign substances, such as sand, bits of wood or metal, or
unchanged fibres of cellulose, &c., which might choke the dies or be
otherwise dangerous. The material issues from the cylinders in the form
of cord or string of the diameter of the holes of the die. The thicker
sizes are cut off, as they issue, into lengths (of about 3 ft.), it
being generally arranged that a certain number of these--say ten--should
have, within narrow limits, a definite weight. The small sizes, such as
those employed for rifle cartridges, are wound on reels or drums, as the
material issues from the press cylinders, in lengths of many yards.

Some of the solvent or gelatinizing material (acetone) is lost during
the incorporating, and more during the pressing process and the
necessary handling, but much still remains in the cordite at this stage.
It is now dried in heated rooms, where it is generally spread out on
shelves, a current of air passing through carrying the acetone vapour
with it. In the more modern works this air current is drawn, finally,
through a solution of a substance such as sodium bisulphite; a fixed
compound is thus formed with the acetone, which by suitable treatment
may be recovered. The time taken in the drying varies with the
thickness of the cordite from a few days to several weeks. For several
reasons it is desirable that this process should go on gradually and
slowly.

After drying, all the various batches of cordite of the same size are
carefully "blended," so that any slight differences in the manufacture
of one batch or one day's output may be equalized as much as possible.
Slight differences may arise from the raw materials, cotton waste or
glycerin, or in the making of these into gun-cotton or nitro-glycerin
respectively. To help in controlling the blending, each "make" of
gun-cotton and nitro-glycerin is "marked" or numbered, and carries its
mark to the cordite batch of which it is an ingredient. The history of
each box of large-sized or reel of small-sized cordite is therefore
known up to the operation of blending and packing. The final testing is
by firing proofs, as in the case of the old gunpowders.

The gun-cotton employed for cordite is made in the usual way (see
GUN-COTTON), with the exception of treating with alkali. It is also
after complete washing with water gentl